Appliance for the production and administration of gas vapor mixtures



March 7, 1950 w. EDMONDSON ETAL 1 2,

APPLIANCE FOR THE PRODUCTION AND ADMINISTRATION OF GAS VAPOR MIXTURESFiled Nov. 26, 1948 2 Sheets-Sheet 1 5 I In venlor March 7, 1950 w.EDMONDSON ETAL 2,499,734

APPLIANCE, FOR THE PRODUCTION AND ADMINISTRATION OF GAS VAPOR MIXTURESFiled Nov. 26, 1948 2 She ets- Sheet 2 Patented Mar. 7, 1950 APPLIANCEFOR THE PRODUCTION AND ADMINISTRATION OF GAS VAPOR MIX- TURES WilliamEdmondson and Wilfred Jones, Oxenhope, Keighley, England ApplicationNovember 26, 1948, Serial No. 62,134 In Great Britain October 6, 1947 4Claims.

This invention relates to a small portable analgesia appliance for theuse of anaesthetists and general practitioners for midwifery and minorsurgical cases where full anaesthesia is not required; also for lightanaesthesia, and it is particularly intended for use as atrichlorethylene air inhaler but may be used for producing andadministering other mixtures.

The invention has for its object to introduce an improved constructionof appliance which will be as small and light as possible consistentwith strength, so that it can be comfortably held in the hand, willprevent any splashing of the liquid, hereinafter referred to as mixturedue to shaking or other causes, from passing in liquid form to thepatient; will maintain consistency of mixture at a given setting in anyposition, that is to say, whether the appliance is held in a vertical,inclined, or horizontal position; will enable the mixture to be adjustedover a Wide range so that differing requirements of the patient may bemet, and so that the anaesthetist or doctor may study the effect ofvarious settings and decide for himself on the one that proves to bemost suitable, and will prevent the setting from being altered by thepatient.

According to this invention, the appliance comprises a small vesselcontaining concentrically arranged perforated tubes encircled by balfleplates surrounded by a circular wick, in combination with a rotary airmixing valve interposed between two ported valve plates and providedwith key actuated means, whereby it can be turned by the key to anyrequired. setting position and locked by the key. An expiratory andnonreturn valve is also incorporated in the appliance and the latter isprovided with a lateral tube which can be plugged directly into astandard face piece.

In order that the said invention may be clearly understood and readilycarried into effect, the same is described more fully with reference tothe accompanying drawings, in which:

Fig. 1 is a view shewing the appliance in section.

Fig. 2 is a plan view of the rotary air mixing valve.

Figs. 3 and 4 are plan views of the ported valve plates. I

A form of appliance for carrying out the invention comprises a tubularcylinder A, closed at one end by a cover plate B that is welded orotherwise fixed to it and provided'with a screw cap C, or other closurefor charging and emptying purposes. The other end is fitted with aported valve plate D that is formed with an axial hole for the passageof a tube E which extends into proximity to the cover plate and isclosed by a flanged plug E Fixed on the latter, between the flange andthe end of the tube, is an annular disc, G which may be slightly dishedand have a flange G extending around its outer edge, and a ring of holesG extending around its inner edge. The flange on the disc points awayfrom the screw cap and is situated a short distance away from thetubular wall and contacts with the inner surface of a tubular wick H,which extends from the cover plate B to the ported valve plate D orthereabouts;

Formed in the tube in proximity to the plug, are one or more holes E andfixed on the tube at each side of the hole or holes, is a conical bafileplate F. Each of these bafiie plates is formed with two cylindricalportions 1?, F and two conical portions F F The cylindrical portion F ofone bafile plate extends around the tube at one side of the hole orholes E and abuts against the flanged disc G, and the other cylindricalportion F of the other baffle plate F extends around the tube at theother side of the hole or holes. The cylindrical portion F on the bafiieplate, last mentioned, forms a seating for an outer tube J whichencircles the tube E. The tube J is formed with one or more holes J 1which occupy a position between the conical bafile plate F in which itis seated, and another conical bafile plate K, which is formed with acylindrical portion K to fit on the tube J on which it is fixed.

The end of this tube terminates a short distance away from the portedvalve plate D in which the inner tube is fixed, and is encircled by twoconical baflle plates L, M. The bafile plate L has an internal flange Lwhich is fixed on the outer tube and an external flange L which may bethe same diameter as the flange G at the end of the inner tube. Theexternal flange L is fixed in a circular recess D in the valve plate Dand supports that end of the outer tube J. The conical baflle plate Mhas an internal flange M which is fixed on the outer tube J and anexternal flange M which extends into proximity to the tubular wall ofthe apparatus and contacts with the tubular wick H. It is also formedwith one or more holes M in proximity to its inner flange, and when thetwo conical flanges are assembled on the outer tube, they form anannular V-shaped channel in which the end of the circular wick mayterminate.

The inner end of the tube E projects through a hole in the valve plateD, and forms a spigot for a tubular boss N which is fixed on the spigotand to the valve plate. Rotatable on the tubular boss between the valveplate D and a smaller fixed valve plate 0, is a rotary valve plate Phaving one or more ports P which may consist of an interrupted circle ofholes formed through it forming two perforated portions between twoblank portions as shewn in Fig. 2. Each of these holes has a radial orother passage P which communicates with the atmosphere. Each fixed valveplate D and may be formed with two curved ports X situated between twoblank portions as shewn in Figs. 3 and 4, the curved ports in one platebeing situated at an angle of 90 to the ports in the other plate so thatthe holes in the rotary valve can be brought wholly or partly intoregistration with the ports in either plate or be entirely closed bybeing presented to the blank portions in either plate.

The rotary valve P can be fixed in any of its adjusted positions bymeans of a screw Q which can be turned by a key to cause its inner endto bear against an annular groove N formed in the tubular boss N onwhich the valve is rotatable and fix the latter in its set position. Forthis purpose the screw may be formed with a hexagonal or othernon-circular hole, and the key, when inserted in the hole, can be usedas a lever for turning the valve to any of its adjusted. positions. Thiskey must be kept by the anaesthetist or other authorised person, so thatthe setting can not be interfered with by the patient or be accidentallydisturbed by an unauthorised person. In the construction shewn in Fig.2, the screw is situated in a headed sleeve Q (Fig. 2) that is placed ina hole formed in the rotary valve P, the head of the sleeve and aportion of the hole being so shaped as to prevent rotation of thesleeve. The latter is threaded internally for a portion of its length toenable the screw to be clamped against the bottom of the groove N butprevent it from coming out of the sleeve and becoming lost. In thisconstruction the key is inserted in the sleeve for turning the valve.The exterior of the rotary valve may be graduated to work in conjunctionwith an indication mark to show the position to which the valve has beenset.

The tubular boss N on which the rotary boss is free to turn is reducedin diameter at N to form a shoulder which acts as a seating for thesmaller valve plate 0 and such portion of reduced diameter passesthrough the valve plate and centralizes it. The peripheral portion ofthe plate enters a circular rebate in the wall of a cap R that issoldered or otherwise secured to it, and this wall is formed with anopening R around which is fixed or formed a lateral tube R which can beplugged directly into a standard face piece.

Fixed on the top of the portion of reduced diameter of the tubular boss,is a valve arrangement S containing a non-return valve T and anexpiratorvalve U, the said arrangement being further supported byentering a circular rebate R in the top of the cap wall. The cap orcover for the latter wall may comprise a metal stamping that is suitablyshaped to fit in the rebate and be secured by turning the end of therebated portion over inwardly, or it may be fixed in any other suitablemanner. The cap is formed with one or more apertures R which communicatewith the atmosphere.

Extending through the fixed disc, tubular boss and cover plate is a tubeV provided with a which projects beyond the fixed disc.

When the appliance is in use, as the patient inspires, air is drawnthrough the branch passages P in the rotary valve, and the stream of airis then divided or controlled according to the setting of such valve.For example, if the latter is set in a position in which mixture off maybe indicated, all the air passes through the branch passages and throughthe port or ports in the smaller fixed valve plate, the port or ports inthe larger fixed valve plate being covered by the blank portion orportions of the rotary valve. If the setting is full on air drawnthrough the branch passages passes through the port or ports in thelarger fixed valve plate, the port or ports in the smaller fixed valveplate being closed by the blank portion or portions of the rotary valve.It then passes between the inner and outer concentric tubes and emergesthrough the hole or holes in the outer tube trichlorethylene chamberwhere it becomes mixed with the trichlorethylene vapour. It then passesthrough the hole or holes in the inner tube, along the latter, past thenonreturn valve and to the patient.

On expiration, the gas passes through the expiratory valve and to theatmosphere through the holes R in the cap.

During expiration, the non-return valve closes and prevents wastage ofthe mixture by expiration through same.

The construction and arrangement of baffle plates prevent the liquidfrom splashing into the face piece in whatever position the apparatus isheld.

Consistency of mixture is obtained for any given setting of the valve,in whatever position the appliance is held.

The adjustment of the mixture percentage is made by inserting the keyinto the set screw. unscrewing the latter slightly rotating the valve,using the key as a lever, and locking by gently tightening the screw.

What we claim as our invention and desire to secure by Letters Patent ofthe United States 1. A portable analgesia appliance of the characterdescribed, including the combination of a casing; a plurality ofperforated tubes concentrically disposed within the casing; a pluralityof baffle plates encircling said perforated tubes; a substantiallycylindrical wick surrounding the baffle plates; a pair of ported valveplates fixed within said casing; and a rotary air-mixing valve disposedbetween said ported valve plates.

2. A portable analgesia appliance of the character described, includingthe combination of a casing; a plurality of perforated tubesconcentrically disposed within the casing; a plurality of baffle platesencircling said perforated tubes; a substantially cylindrical wicksurrounding the baffle plates; a pair of ported valve plates fixedwithin said casing; a rotary air-mixing valve disposed between saidported valve plates; and an expiratory non-return valve operably mountedin said casing.

13. A portable analgesia appliance of the character described, includingthe combination of a casing; a plurality of perforated tubesconcentrically disposed within the casing; a plurality of baffle platesencircling said perforated tubes; a substantially cylindrical wicksurrounding the baiiie plates; a pair of ported valve plates fixedwithin said casing; a rotary air-mixing valve disposed between saidported valve plates; a key; and a key actuated means for turning therotary air-mixing valve to any selected position by means of the key andlocking the latter valve 7 in the selected position by said key.

6 ing the latter valve in the selected position by said key.

WILLIAM EDMONDSON. WILFRED JONES.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Name Date Bloomheart July 2, 1940 Number 2,206,688

